ABSTRACT
An efficient and simple route for preparation of substituted 1,5-benzodiazepine-2-one containing peptoid backbone is presented. The classical Ugi reaction is considerably extended by application of o-phenylenediamine and diketene as amine and oxo component. 1,3-Dihydro-1,5-benzodiazepine-2-one is generated in situ from these two building blocks combined with isocyanide and aromatic or aliphatic carboxylic acid to assemble the multifunctionalized titled scaffold in high yields. The reaction is performed in the mixture of toluene/CH(2)Cl(2) under reflux condition without catalyst. Conformational isomerism is seen in the solution phase because of restricted free rotation around amide and C-CO bands due to steric bulk of substitutions. In single crystal state, the product is found to possess dimeric structure arising from intermolecular hydrogen bonding.
